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Diffstat (limited to 'deps/v8/src/key-accumulator.cc')
-rw-r--r-- | deps/v8/src/key-accumulator.cc | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/deps/v8/src/key-accumulator.cc b/deps/v8/src/key-accumulator.cc new file mode 100644 index 0000000000..91b014aacd --- /dev/null +++ b/deps/v8/src/key-accumulator.cc @@ -0,0 +1,263 @@ +// Copyright 2013 the V8 project authors. All rights reserved. +// Use of this source code is governed by a BSD-style license that can be +// found in the LICENSE file. + +#include "src/key-accumulator.h" + +#include "src/elements.h" +#include "src/factory.h" +#include "src/objects-inl.h" + + +namespace v8 { +namespace internal { + + +KeyAccumulator::~KeyAccumulator() { + for (size_t i = 0; i < elements_.size(); i++) { + delete elements_[i]; + } +} + + +Handle<FixedArray> KeyAccumulator::GetKeys(GetKeysConversion convert) { + if (length_ == 0) { + return isolate_->factory()->empty_fixed_array(); + } + // Make sure we have all the lengths collected. + NextPrototype(); + + // Assemble the result array by first adding the element keys and then the + // property keys. We use the total number of String + Symbol keys per level in + // |level_lengths_| and the available element keys in the corresponding bucket + // in |elements_| to deduce the number of keys to take from the + // |string_properties_| and |symbol_properties_| set. + Handle<FixedArray> result = isolate_->factory()->NewFixedArray(length_); + int insertion_index = 0; + int string_properties_index = 0; + int symbol_properties_index = 0; + // String and Symbol lengths always come in pairs: + size_t max_level = level_lengths_.size() / 2; + for (size_t level = 0; level < max_level; level++) { + int num_string_properties = level_lengths_[level * 2]; + int num_symbol_properties = level_lengths_[level * 2 + 1]; + if (num_string_properties < 0) { + // If the |num_string_properties| is negative, the current level contains + // properties from a proxy, hence we skip the integer keys in |elements_| + // since proxies define the complete ordering. + num_string_properties = -num_string_properties; + } else if (level < elements_.size()) { + // Add the element indices for this prototype level. + std::vector<uint32_t>* elements = elements_[level]; + int num_elements = static_cast<int>(elements->size()); + for (int i = 0; i < num_elements; i++) { + Handle<Object> key; + if (convert == KEEP_NUMBERS) { + key = isolate_->factory()->NewNumberFromUint(elements->at(i)); + } else { + key = isolate_->factory()->Uint32ToString(elements->at(i)); + } + result->set(insertion_index, *key); + insertion_index++; + } + } + // Add the string property keys for this prototype level. + for (int i = 0; i < num_string_properties; i++) { + Object* key = string_properties_->KeyAt(string_properties_index); + result->set(insertion_index, key); + insertion_index++; + string_properties_index++; + } + // Add the symbol property keys for this prototype level. + for (int i = 0; i < num_symbol_properties; i++) { + Object* key = symbol_properties_->KeyAt(symbol_properties_index); + result->set(insertion_index, key); + insertion_index++; + symbol_properties_index++; + } + } + + DCHECK_EQ(insertion_index, length_); + return result; +} + + +namespace { + +bool AccumulatorHasKey(std::vector<uint32_t>* sub_elements, uint32_t key) { + return std::binary_search(sub_elements->begin(), sub_elements->end(), key); +} + +} // namespace + +bool KeyAccumulator::AddKey(Object* key, AddKeyConversion convert) { + return AddKey(handle(key, isolate_), convert); +} + + +bool KeyAccumulator::AddKey(Handle<Object> key, AddKeyConversion convert) { + if (key->IsSymbol()) { + if (filter_ == SKIP_SYMBOLS) return false; + return AddSymbolKey(key); + } + // Make sure we do not add keys to a proxy-level (see AddKeysFromProxy). + DCHECK_LE(0, level_string_length_); + // In some cases (e.g. proxies) we might get in String-converted ints which + // should be added to the elements list instead of the properties. For + // proxies we have to convert as well but also respect the original order. + // Therefore we add a converted key to both sides + if (convert == CONVERT_TO_ARRAY_INDEX || convert == PROXY_MAGIC) { + uint32_t index = 0; + int prev_length = length_; + int prev_proto = level_string_length_; + if ((key->IsString() && Handle<String>::cast(key)->AsArrayIndex(&index)) || + key->ToArrayIndex(&index)) { + bool key_was_added = AddIntegerKey(index); + if (convert == CONVERT_TO_ARRAY_INDEX) return key_was_added; + if (convert == PROXY_MAGIC) { + // If we had an array index (number) and it wasn't added, the key + // already existed before, hence we cannot add it to the properties + // keys as it would lead to duplicate entries. + if (!key_was_added) { + return false; + } + length_ = prev_length; + level_string_length_ = prev_proto; + } + } + } + return AddStringKey(key, convert); +} + + +bool KeyAccumulator::AddKey(uint32_t key) { return AddIntegerKey(key); } + + +bool KeyAccumulator::AddIntegerKey(uint32_t key) { + // Make sure we do not add keys to a proxy-level (see AddKeysFromProxy). + // We mark proxy-levels with a negative length + DCHECK_LE(0, level_string_length_); + // Binary search over all but the last level. The last one might not be + // sorted yet. + for (size_t i = 1; i < elements_.size(); i++) { + if (AccumulatorHasKey(elements_[i - 1], key)) return false; + } + elements_.back()->push_back(key); + length_++; + return true; +} + + +bool KeyAccumulator::AddStringKey(Handle<Object> key, + AddKeyConversion convert) { + if (string_properties_.is_null()) { + string_properties_ = OrderedHashSet::Allocate(isolate_, 16); + } + // TODO(cbruni): remove this conversion once we throw the correct TypeError + // for non-string/symbol elements returned by proxies + if (convert == PROXY_MAGIC && key->IsNumber()) { + key = isolate_->factory()->NumberToString(key); + } + int prev_size = string_properties_->NumberOfElements(); + string_properties_ = OrderedHashSet::Add(string_properties_, key); + if (prev_size < string_properties_->NumberOfElements()) { + length_++; + level_string_length_++; + return true; + } else { + return false; + } +} + + +bool KeyAccumulator::AddSymbolKey(Handle<Object> key) { + if (symbol_properties_.is_null()) { + symbol_properties_ = OrderedHashSet::Allocate(isolate_, 16); + } + int prev_size = symbol_properties_->NumberOfElements(); + symbol_properties_ = OrderedHashSet::Add(symbol_properties_, key); + if (prev_size < symbol_properties_->NumberOfElements()) { + length_++; + level_symbol_length_++; + return true; + } else { + return false; + } +} + + +void KeyAccumulator::AddKeys(Handle<FixedArray> array, + AddKeyConversion convert) { + int add_length = array->length(); + if (add_length == 0) return; + for (int i = 0; i < add_length; i++) { + Handle<Object> current(array->get(i), isolate_); + AddKey(current, convert); + } +} + + +void KeyAccumulator::AddKeys(Handle<JSObject> array_like, + AddKeyConversion convert) { + DCHECK(array_like->IsJSArray() || array_like->HasSloppyArgumentsElements()); + ElementsAccessor* accessor = array_like->GetElementsAccessor(); + accessor->AddElementsToKeyAccumulator(array_like, this, convert); +} + + +void KeyAccumulator::AddKeysFromProxy(Handle<JSObject> array_like) { + // Proxies define a complete list of keys with no distinction of + // elements and properties, which breaks the normal assumption for the + // KeyAccumulator. + AddKeys(array_like, PROXY_MAGIC); + // Invert the current length to indicate a present proxy, so we can ignore + // element keys for this level. Otherwise we would not fully respect the order + // given by the proxy. + level_string_length_ = -level_string_length_; +} + + +void KeyAccumulator::AddElementKeysFromInterceptor( + Handle<JSObject> array_like) { + AddKeys(array_like, CONVERT_TO_ARRAY_INDEX); + // The interceptor might introduce duplicates for the current level, since + // these keys get added after the objects's normal element keys. + SortCurrentElementsListRemoveDuplicates(); +} + + +void KeyAccumulator::SortCurrentElementsListRemoveDuplicates() { + // Sort and remove duplicates from the current elements level and adjust. + // the lengths accordingly. + auto last_level = elements_.back(); + size_t nof_removed_keys = last_level->size(); + std::sort(last_level->begin(), last_level->end()); + last_level->erase(std::unique(last_level->begin(), last_level->end()), + last_level->end()); + // Adjust total length by the number of removed duplicates. + nof_removed_keys -= last_level->size(); + length_ -= static_cast<int>(nof_removed_keys); +} + + +void KeyAccumulator::SortCurrentElementsList() { + if (elements_.empty()) return; + auto element_keys = elements_.back(); + std::sort(element_keys->begin(), element_keys->end()); +} + + +void KeyAccumulator::NextPrototype() { + // Store the protoLength on the first call of this method. + if (!elements_.empty()) { + level_lengths_.push_back(level_string_length_); + level_lengths_.push_back(level_symbol_length_); + } + elements_.push_back(new std::vector<uint32_t>()); + level_string_length_ = 0; + level_symbol_length_ = 0; +} + + +} // namespace internal +} // namespace v8 |